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<table width="100%" summary="page for RadioactiveTwins"><tr><td>RadioactiveTwins</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Comparing Twins Ability to Clear Radioactive Particles</h2>

<h3>Description</h3>

<p>Experiment comparing twins (one urban, one rural) ability to clear airborne radioactive particles from their lungs
</p>


<h3>Format</h3>

<p>A data frame with 30 observations on the following 3 variables.
</p>

<dl>
<dt><code>TwinPair</code></dt><dd><p>Identifies the twin pairs (1 to 15)</p>
</dd>
<dt><code>Env</code></dt><dd><p>Residential environment  (<code>Rural</code> or <code>Urban</code>)</p>
</dd>
<dt><code>Rate</code></dt><dd><p>Clearance rate (percentage radioactive particles remaining after one hour)</p>
</dd>
</dl>



<h3>Details</h3>

<p>To assess lung health, the scientists measured &quot;tracheobronchial clearance rate,&quot; that is, in English, &quot;How fast do your lungs get rid of nasty stuff?&quot;  Each subject agreed to inhale an aerosol of radioactive Teflon particles.  A Geiger counter held to the chest measured the radioactivity just after inhaling, and again one hour later.  The clearance rate was the percentage of radioactivity remaining &ndash; the lower the better.  Subjects were 15 sets of identical twins, each pair with one twin living in an urban environment and the other in a rural environment.
</p>


<h3>Source</h3>

<p>Per Camner MD &amp; Klas Philipson MSc (1973) &quot;Urban Factor and Tracheobronchial Clearance,&quot; Archives of Environmental Health: An International Journal, 27:2, 81-84, DOI: 10.1080/00039896.1973.10666323
Link to the article: https://doi.org/10.1080/00039896.1973.10666323
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